A review of next generation bifacial solar farms: predictive modeling of energy yield, economics, and reliability

Abstract

Photovoltaic (PV) cell technology has made great progress over the past few decades, bringing the PV energy cost down to a point where it is competitive to conventional electricity prices. While monofacial panels have historically dominated the market, recent developments in the manufacturing of bifacial panels (collecting light from both faces) have made them accessible for commercial applications. It is therefore imperative to define the design principles so that the steeply expanding market of bifacial modules and PV farms stays on an efficient path. In this paper, we will discuss physics-based models for these next-generation bifacial PV farms for analyzing yield and costs. Besides the conventional farm configurations, tracking systems are gaining market shares aiming to enhance the yield at a lower cost. Within ± 30 ∘ latitudes, we predict a 20%-30% energy gain for fixed-tilt bifacial over monofacial modules and an additional 20%–40% gain for single-axis bifacial tracking. Compound systems such as agrophotovoltaics and floating PV applications may be the possible future for a sustainable merger of food-water-energy systems. We show a competing relation between active light collection on crops and energy yield in an agrophotovoltaics system vs panel density—the final design will be decided by the crop yield or light usage efficacy constraint. The output reliability in terms of soiling and module degradation is also explained in this paper. Solar farms are expected to see 2%–5% loss in revenue in Asia and the Middle East even after optimal cleaning. Additionally, the bifacial modules degrade ∼0.5%–0.6%/year. While there have been several physics-based degradation analyses, the bifacial technology lacks a large enough data set of long-term degradation studies for accurate predictions. The combined economics of reliability against yield will decide the viability of the next generation bifacial PV industry.

Land-use intensity of electricity production and tomorrow’s energy landscape

“…For example, the manufacturing and construction of bifacial PV (light collected from both sides of the panel surface) is driven by estimates of 20–40% electricity gains over monofacial panels, which could ostensibly drive smaller power plant footprints to meet finite electricity needs. However, the exponential increases in electricity demand globally and the nascent state of the technology’s economic and reliability outcomes mean that impacts on real-world LUIE are yet to be determined [ 79 ].…”

Efficiency Enhancement of Tilted Bifacial Photovoltaic Modules with Horizontal Single-Axis Tracker—The Bifacial Companion Method

“…Lazaroiu et al [15] studied the power generation gain and energy consumption of a photovoltaic system with solar tracking, and the results indicated a significant growth in the power production during morning and evening. Patel et al [21] showed that when the geographic latitude was lower than 30 • , the annual power generation of a single-axis tracking system was higher than that of an optimal fixed-tilt mounted system by 25-45%. Regarding the solar tracking method, based on the traditional maximum power point tracking method (MPPT) [22], Clifford and Eastwood [23] proposed a novel passive solar tracker, whose power generation gain could reach 30%.…”

Improving solar photovoltaic installation energy yield using bifacial modules and tracking systems: An analytical approach

“…28 The market share of tracking system is on the rise because it has the ability to enhance the energy yield at a lower cost. 24 The solar trackers are in charge of keeping the surface of the PV modules nearly perpendicular to direct irradiance almost all of the time, allowing them to collect a greater amount of irradiance. 29 Single-axis tracking and dual-axis tracking are the two main categories of solar tracking systems.…”